Double glazed window



Deci 1., 1936.

F. GELSTHARP DOUBLE GLAZED WINDOW Filed Oct. 5, 1955 v INVENToR./Q'socQ/c/c GDL-Lrwwrp BY Y A T ORNEYS.

` 4L0 ity readily accessible.

UNITED STATES amari PATENT OFFICE DOUBLE GLAZED WINDOW FrederickGelntharp, Tarentum, P'a., asslgnor to Pittsburgh Plate Glass Company,

Allegheny `County, Pa., a corporation of Pennsylvania ApplicationOctober 5, 1935, Serial No. 43,729

3 Claims.

The invention relates to double glazed windows particularly for use inconnection with railway passenger cars. It is necessary with doubleglazed windows that the gas between the panes 5 (air, nitrogen or otherinert gas) should be mainphere and supplied with dry Sas when theinstala lation is made. This prevents any clouding of the glass when theinstallation is rst made, but it is practically impossible to maintainthe seal at the edges of the panes over any considerable period of time,so that infiltration of air carrying moisture occurs, resulting inclouding ofthe glass. This condition calls for the removal of the unitfrom its frame, a renewal of the seal, and a replacement of the moistgas with a dry one. The

tendency to leakage and infiltration is further increased due to changesin atmospheric pressure to which the car is often subject, as thiscauses bending of the sheets in and out incident to relative changes inpressure in the atmosphere, as compared with the pressure between theglass sheets. The present invention is designed to remedy thedifficulty, as above 'set forth, and to provide a construction in whichclouding of the inner faces of the glass sheets is avoided or remedieddespite any failure of the seal which may occur at the edges of theglass sheets.

Briefly stated, this is accomplished by the use of a piping systemconnectedl to the spaces between the pairs of glass sheets in serieswith circulating means, such as a fan or pump and a dehydrating unit,the piping being suitably located -in the walls of the car, and thecirculating and dehydrating means being located in a space or cav- Whenany or all'of the windows show clouding, the system is operated tocirculate and dry the air or other gas, after which each unit maybe cutoff from the system, if desired. Also associated'with the circulationsystem is an expanding device. such as a sylphon,

which tends to equalize the pressure inside the units with that outside,thus reducing the tendency to leakage-and also to breakageintranscontinental cars, in which large variations in .atmosphericpressure occurs due to changes in elevation. The one system of pipingthus takescare of the circulation for dehydration and equalizingpressure, and avoids any requirement for removing the glazing units fromthe structure in which they are mounted in order to recondition them.

(Cl. 2II-56.IS)L

-One embodiment of the invention is illustrated in the accompanyingdrawing. wherein: i.

Figure 1 is a diagrammatic sidev elevation view showing theconstruction. And Fig. 2 is a vertical section through one oi the units.5

Referring to the drawing, YI and i are double glazed units constitutinga part of a series of. such units `as used in the side of a passengerearA Each of these units consists of a pair of glass sheets 3 and 4,spaced apart as indicated in Fig. 2, by u strips of material II, such asrubber or other suitable material which will form a seal with the glass.

`Around the periphery of the glass sheets is a frame 6 preferably ofsheet metal, which applies the compressive force upon the periphery oithe 15 unit. I isone side of the car framing, and 8 is the other side,the unit being held removably in position by means of strips 9 of sheetmetal secured in position by means oi screws or bolts.

The particular character of the mounting of the 20 unit is immaterial inso far as the present invention is concerned. .I

Extending longitudinally of the structure above and below the windowsare the pipes I0 and II which communicate with the spaces between the 25glass sheets through the connections I2 and I3. Valves I4 and I5 serveto cut on the spaces between the glasses from the pipes It and II whenit is desirable to do this. Lying in a circuit which includes the pipesI 0 and II is a circulating fan 30 or pump I6 and a pair of dehydratingtanks I l, I1. 'Ihe tanks contain a suitable dehydrating material, suchas activated alumina or silica gel, which will remove the moisture fromthe gas circulated therethrough. These dehydrating ele- 3f ments may beof various designs well vknown in the dehydrating art and are preferablyprovided with heaters for drying out the dehydrating material from timeto time.

Two tanks are employed so that in service their use may be alternated,thus permitting one of the tanks to be regenerated or renewed while theother tank remains in service. Suitable valves I 8, I9, 20, and 2| areprovided so that the circulation may be switched through either tankdepending upon which one is used. Connections 22 are'also providedleading to the atmosphere and carrying valves 23, so that thecirculation may be directed to the outer air when one of the tanks isbeing regenerated. 5

The line I0 is also provided with a filter 24 for catching anydirt ordust in the system, and the line II' is provided with a sylphon 25 orother suitable expanding container for permitting at least( a. partialequalization of the pressure be- 55 tween the glass panes and theatmosphere. When the atmospheric pressure on the panes is reduced, theexcess pressure ows into the syl- `phon so that the windows do not`bulge outward,

as would otherwise be the case, andwhen pressure on the panes by theatmosphere is increased, the sylphon contracts and forces air or gasinto the spaces between the glass sheets. This reduces any tendency tobreaking of the windows and also tends to prevent leakage at the pointsat which the glass sheets are sealed since the constant bending in andout of the glass sheets tends to impair the seal.

When the inner surfaces of any lof the glass sheets become clouded, dueto infiltration of moisture from the atmosphere, the operator starts thefan or pump I6 and a circulation of gas is secured from the line I tothe line Il through the window spaces, and this circulating gas flowsthrough the fan or pump and through one of the dehydrating tanks I1,thus carrying any moisture-laden gas from the spaces between the windowsand dehydrating it, 4the moistureladen gas being replaced by a dry gasso that the clouding on the glasses soon disappears. The units may allbe reconditioned at one time, or may be individually reconditioned bymanipulating the valves I4 and l5 to meet requirements. The fan or pumpIB may be driven in any suitable way, but is ordinarily driven when usedin a car construction by an electric motor supplied with current fromthe storage batteries of the car.

By the usev of this apparatus any requirement for removing the doubleglazed units from the car for reconditioning is avoided, such removaland reconditioning being a. matter of very considerable expense andinconvenience in a construction of this type. lThe invention has itslargest application in connection With car constructions, but may beused to advantage in other structures employing a large number ofglazing units which are so located that they may be convenientlyconnected to a piping system.

What I claimed is:

1. In combination with a wall structure comprising a plurality ofwindows each consisting of a pair of glass sheets spaced apart andprovided with sealing means between their margins, a piping system inthe wall structure connected with the spaces between the pairs of glasssheets, means for causing a circulation through the piping system andsaid spaces, dehydrating means located in the line of ow through saidsystem and a readily expansible container connected to the pipingsystem.

2. In combination with a wall structure comprising a plurality ofwindows each consisting of a pair of glass sheets spaced apart andprovided with sealing means between their margins. a piping system inthe wall structure connected with the spaces between the pairs of glasssheets. means for causing a circulation through the piping system andsaid spaces, valves in the piping system whereby each unit may be closedoit with respect to the piping system, dehydrating means located in theline of flow through said system. and a. readilyexpansible containerconnected to said piping system.

3. In combination with a wall structure comprising a plurality ofwindows each consisting of a pair of glass sheets spaced apart andprovided with sealing means between their margins, a piping system inthe wall structure connected with the spaces between the pairs of glasssheets,

means for causing a circulation through the piping system and saidspaces, dehydrating. means located in the line of flow through saidsystem.

.and a sylphon. connected to said piping system.

FREDERICK GELBTHARP.

